金沙江攀枝花河段土壤重金属污染状况及生态风险评价

Soil heavy metal pollution and ecological risk assessment in Panzhihua reach of Jinsha River

为清晰了解金沙江攀枝花河段土壤重金属污染状况,以丰、平、枯不同水期下金沙江攀枝花河段岸边土壤为研究对象,采用单因子污染指数法、内梅罗综合污染指数法以及潜在生态风险指数法对金沙江攀枝花河段土壤重金属污染状况以及可能存在的生态风险进行评价,并提出了相关风险管控建议.研究结果表明,丰、平、枯不同水期下V,Cd,Cu,Ni等重金属质量含量均值超过四川省表层土壤背景值;丰水期与枯水期下重金属内梅罗综合污染指数均值分别为3.10,3.14,综合污染等级达到Ⅴ级重度污染,平水期下重金属内梅罗综合污染指数均值为2.94,综合污染等级达到Ⅳ级中度污染,土壤中Cd,V污染值得进一步关注;丰、平、枯不同水期下金沙江攀枝花河段岸边土壤重金属的潜在生态风险系数均值分别为144.04,110.88和147.15,总体呈现轻微生态风险,重金属Cd存在的危害较为严重,潜在生态风险指数分别为103.92,84.81和111.71,呈现强生态风险,Cd存在的生态风险值得进一步去关注.

To clearly understand the heavy metals pollution of the soil in the Panzhihua reach of the Jinsha River,the bank soil of which in wet,normal and dry periods were taken as the research objects.In addition,the single-factor pollution index method,the Nemerow comprehensive pollution index method,and the potential ecological risk index method were used to evaluate the pollution state of soil heavy metals and possible ecological risk in the Panzhihua reach of the Jinsha River.Apart from that,relevant risk management and control recommendations are put forward.The results show that the average content of heavy metals such as V,Cd,Cu,Ni in different periods of wet,normal and dry water levels exceed the background value of the surface soil in Sichuan Province;the mean values of the heavy metals Nemerow comprehensive pollution index in the wet and dry seasons are 3.10 and 3.14,respectively,the comprehensive pollution level reaches levelⅤheavy pollution,the average value of the heavy metal Nemerow comprehensive pollution index in the normal water period is 2.94,the comprehensive pollution level reaches levelⅣmoderate pollution,Cd and V pollution in soil deserve further attention;the average values of the potential ecological risk coefficients of heavy metals in the bank soil of the Panzhihua reach of the Jinsha River in wet,normal,and dry periods are 144.04,110.88,and 147.15,respectively,showing a slight ecological risk in general,the harm of heavy metal Cd is more serious,and the potential indexes of ecological risk are 103.92,84.81 and 111.71,respectively,presenting strong ecological risk,the ecological risk of Cd deserves further attention.